Multiple variable condenser



Dec. 1i 1925.

s. COHEN MULTIPLE VARIABLE CONDENSER Original Filed March 14, 1925 4Sheets-Shea?I 1 @a l, l;

Dec. 1, 1925. 1,563,893

S. COHEN MULTIPLE VARIABLE CONDENSER original Filed March 14. 1925 4sheets-sheet 2 I INVENTOR Haifa/@ (y0/26W,

Dec. 1 I 1925. 1,563,893

' S. COHEN MULTIPLE VARIABLE CONDENSER Original Filed March 14, 1925 4Sheets-Sheetl 5 mvtujron Aga/aff y0/IPH.

Dec, 1, 1925. 1,563,893

. S. COHEN MULTIPLE VARIABLE CONDENSER Original Filed. MarGh 14, 1925 4Sheets-Sheet 4 Patented Dee 1,1925.

SAMUEL COHEN, OF BROOKLYN,

CORPORATION, orY NEW YORK,- N.' Y., A

NEW YORK, ASSIGNOR T GENERAL INSTRMENT coRronA'rroN or NEW YORK.

MULTIPLE VARIABLE' coNDENsEn. l

Qriginal application led March 14, 1925, Serial No. 15,516. Divided andthis -application filed September f 25, 1925. Serial to.v 58,635.

The object of my invention is to provide a multiple variable condenserconstruction in which a plurality of sets of rotor and stator plates arearranged within a. commonframe, with the sets of rotor plates mountedupon a central shaft and arranged to-interleave with the sets of statorplates, 'with means for insulating one group of stator plates from anadjacent .group of statorV plates by insulators extendmg between thecondenser frame and the sets of stator, plates where the insulators arelaterally positioned in the frame and in lines substantially parallel toplanes passing through 'the stator plates.

The broad subject matter of my invention is more particularly set forthin my copending application for Letters Patent Serial No. 15,516, tiledMarch 14, 1925.

Other and further objects of my invention will be understood from thespecification hereinafter following by reference to the accompanyingdrawings, wherein:

Figure 1 is a perspective view of one con'- struction of my,` multiplevariable condenser; Fig. 2 showssa front view of the multiple variablecondenser construction illustrated in Fig. 1; Fig. 3 is an end view 'ofthe multiple condenser structure of Fig. 2; Fig. '4 is a sectional viewthrough the multiple variable condenser taken on line 4-4 of Fig-2; Fig.5 is a front view of a modified form of multiple yariable condenser conpstructed in accordance with my invention and showing the independentsets of. stator plates supported by insulation material undercompression; Fig. 6 isa side view of the multiple variable condenserillustrated '1n No. 15,516, led March 14,V

Fig. 5 showing the arrangement of the sets of rotorV plates on thecentralrotatable shaft for balancing the sets of plates throughout thedistance of rotation thereof; Fig. 7 is a cross sectional view takenonline 7.7 of Fig. 5 through the balanced condenser constructionillustrated in Fig. 5; Fig. 8 is a detail view showing one method ofsupporting the stator. plates by pedestal insulators; Fig. 9 is afragmentary view illustrating a modified method of supporting the indeendent sets of stator plates on quartz insu ators interposed between thesets of stator plates p and the frame of the multiple variablecondenser; and Fig. 10 iS an enlarged cross sectional view taken throughone of the supporting frame members of the variable condenser in whichthe insulating members are secured. v

My present invention utilizes some of the principles set forth in myco-pending application for` Letters Patent of the' United StatesentitledVariable condenser, iled No- Y vember 8, 1924 and identiied bySerial No. 748,708. My compact variable condenser, unit includingpresent invention provides a a condenser frame and a plurality ofindependent stator units which are substantially insulated from thecondenser frame and from each other in the frame under compression. Therotor by insulators securedv plates are positioned vupon a central shaftjournaled -in the condenser frame and may be interleaved with theindependent sets ofy stator plates in such manner that the con-y denseris mechanically balanced so that the rotor plates may be moved withprecision and accurately adjusted in capacity, whlch capacity isaccurately maintained for any desired period of time. The condenserframe and the sets ofistator plates form a substantial unit by reason ofa double pedestal mounting sltuated at opposite ends of thel statorplates. The overall dimensions of the condenser unit may be relativelysmall and ts conveniently within a radio receiver f or the control of amultiple numbe-rof circuits therein.

lates upon the ,central such that the movement of the shaft 1s balancedin such manner that for different de? ees of rotation of the shaft andvariation 1n capacity between the sets of plates, precision adjustmentof the instrument 1s possi# The arrangement of the 'rotor rotatableshaft' '1s ble with the. accurate maintenence of the `capacity seselected.

Referring more particularly to the drawings, reference character ldesignates one and 11.

end frame of the condenser, while reference character 2 designates anopposite end frame for thg condenser, connected by frame members 3, 4,5, 6 and 7. The end frame members 1 and 2 are provided with eX- tendedportions at opposite sides which are bridged by the strip-like members8, 9, 10, Between the strip-like members 8 and lOthere is secured undercompression alternate conductive blocks 12, 14 and 15, and pedestalinsulators 16, 17, 18 and 19. Between the strip-like members 9 and 11there is interposed under compression alternate conductive blocks 20, 21and .22, and pedestal insulators 23, 24, 25 and 26. The blocks 12, 14,15, 20, 21 and 22 are grooved as represented atk 27 to receive oppositeends of the sets of stator plates 28, 29 and 30.

vThe slotting of each of the blocks enables the stator plates to berigidly secured in spaced relationship.l The spacing of the sets ofstator plates is such that the pedestal insulators fully protect one setot' stator plates against potentials existing across the circuitsincluding the other sets of stator plates. The rotorplates are disposedin sets designated at 31, 32 and 33 upon a central shaft 34 journaled at35 -in the end plate 1 and at 36 in the opposite end plate 2. The rotorplates may be simultaneously interleaved with the separate sets ofstator plates as has been more clearly represented 1n Fig. 1 of thedrawings. The rotation of the central shaft 34 is governed by the endspring member 37 and connection to all of the stator plates may be madefrom any part of the grounded frame. Independent connections may betaken from the separate sets of stator plates 28, 29 and 30 from thelugs designated at 38, 39 and 40. In t-he condenser constructionillustrated in Figs. 5 to 10 the end plates 1 and 2 are connectedbylongitudinally extending frame members 3, 4, 5 and 6 and pairs of bars41, 42, 43 and 44. lAt intervals along the length ot the bars, the barsare drilled as represented at 58 in Fig. 10 and countersunk on eachside'thereof as represented at 59 and 60. In one of the countersunkportions the ends of porcelain insulators 61 or quartz insulators 62,`as designated in Figs. 8 and 9 respectively are secured. In the case otedestal insulators of porcelain,these insuators are molded with a vboreextending through the center with internal screw threads toy receive amachine screw 63, the head of which may be positioned flush with thesurface of the supporting bar by'itting within the countersunk portion59. The location of the bore internally of the pedestal insulatorincreases the surface area 'pedestal insulators 61 or the quartzinsulator 62 enter a cup shaped device 64 which is secured by screw 65to the rear face et the conductive block 21. A pair et' insulators arethus positioned at opposite ends 0f the stator plates in such mannerthat sets of statorv plates are rigidly secured in position and theplates positively spaced apart. The set of stator plates are positionedalternately along -the condenser' frame as illustrated in Fig. 6, thatis, the stator plates 28 are rigidly positioned at one side of thecondenser frame between vconductive blocks 12 and 20. The stator plates29A are positioned at the opposite side of the` condenser frame betweenconductive blocks 14 and 21. Similarly, the sets of stator plates 30 arepositioned on the op-. posite side of the condenser frame from statorplates 29, and on the same side with stator plates 28'. The statorplates 30 are secured, in position between conductive blocks 15 and 22under compression and supported upon insulators as hereinbetoredescribed Other sets of stator plates 51 and 53 are mounted in thecondenser frame on the same side as that on which stator plates 29 aremounted, and between conductive blocks 45 and 46, and 49 and 50respectively, while a set oi stator plates 52 is mounted on the oppositeside of the lcondenser frame between conductive blocks 47 and 48. Thecentral shaft 34 is journaled at opposite ends at 35 and 36 and carriessets of rdtor plates designated at 31,32, 33, 54, 55, and.56, whichcooperate with the hereinbefore referred to independent sets of statorplates. By the arrangement of the rotor plates on the central shaft 34,I provide a condenser which is self-balancing and whichl doesnot-require the use et weights for maintaining the position of the rotorplates. The provision of a pair of insulating members at opposite endsof the stator plates insures the plates against twisting and therebyprovides a substantial condenser construction.

It will be observed that the rotor plates are so arranged that when themutual capacity between one set of rotor and stator plates is decreasingthe mutual 'capacity hetween another set of rotor plates and statorplates is increasing. The fact that the sets of stator plates areindependent one from the other enables the stator plates to be'connected in a variety of electrical circuits,

but my invention finds particular applicathe scope of the appendedclaims.

IVhat I claim and desire to secure by Letters Patent of the UnitedStates is as follows l. A multiple variable condenser coinprising incombination a pair of end-plates,

frame members interconnecting 'said end plates, a plurality ofindependent sets of stator plates, insulation means interposed betweensaid frame members and each ot' said sets of stator plates, whereby oneset of said stator plates is substantially insulated from another set ofsaid stator plates, a shaft journaled in said end plates, sets of rotorplates carried by said shaft and arranged to be interleaved between saidsets of stator plates whereby the mutual capacity between said sets ofplates may be simultaneously varied by rotation of said central shaft. if

2. A multiple variable condenser comprising in combination a pair of endplates, frame members interconnecting said end plates, a plurality' ofvindependent sets of stator plates, conductive blocksy supporting saidstator plates in spaced relationship one a vfrom another, insulatorsinterposed between said conductive blocks and said frame members wherebysaid statorv plates may be positively supported in spaced relationshipin a group independent from another group of stator plates within saidframe members, aicentral rotatable shaft journaled in said end plates,sets of rotor plates carried by said rotatable shaft and adapted to beinterleaved between said stator latesI for varying the capacity betweensald sets of plates simultaneously upon rotation of said central shaft.

A multiple variable condenser, coinprising in combination a pair of endplates,

frame members interconnectin said end plat-es, a plurality of indepenent sets'of stator plates, grooved conductive blocks adapted to receiveopposite ends of said stator plates and support said stator plates in'spaced relationship, insulators interposed between said conductiveblocks and said frame members adjacent opposite ends 'of said statorplates and in a line parallel to a 'plane passing through said statorplates, a central rotatable shaft journaled in said end plates, sets ofrotor plates carried by said rotatable shaft and adapted to beinterleaved between said stator plates for varying the capacity betweensaid sets of plates simultaneously upon rotation of said central shaft.

4. A multiple variable condenser comprisiig in combination a pairy ofendvplates, frame members interconnecting said end plates, a pluralityof independent sets of stator plates. conductive blocks supporting saidstator plates in spaced relationship one from another, al pair ofinsulators interposed between said conductive blocks at opposite ends ofsaid stator plates and said frame members for rigidly supporting saidstator plates within said frame members, a central rotatable Ishaftjournaled in said end plates, sets of rotor plates carried by saidrotatable shaft and adapted to be interleaved between said stator platesfor varying the capacity between said sets of plates simultaneously uponrotation of said central shaft.

5. A multiple variable condenser comprising in combination a pair of endplates, frame member interconnecting opposite ends of .said end plates,lconductive blocks carried by oppositely positioned .frame members forsecuring' groups of stator plates therebetween, with said groups ofstator .plates alternately positioned along the length of said framemembers, insulators interposed between Said conductive blocks. and saidframe members and secured under compression in planes parallel with theplanes of said stator plates, a central rotatable shaft journaled insaid end plates, groups of rotor plates carried by said central shaftand arranged to be interleaved with said groups of stator plates forsimultaneously varying the mutual capacity between said sets of plates.i' SAMUE L COHEN.

